Data from: Natural selection on thermal preference, critical thermal maxima and locomotor performance

Climate change is resulting in a radical transformation of the thermal quality of habitats across the globe. Whereas species have altered their distributions to cope with changing environments, the evidence for adaptation in response to rising temperatures is limited. However, to determine the potential of adaptation in response to thermal variation, we need estimates of the magnitude and direction of natural selection on traits that are assumed to increase persistence in warmer environments. Most inferences regarding physiological adaptation are based on interspecific analyses, and those of selection on thermal traits are scarce. Here, we estimate natural selection on major thermal traits used to assess the vulnerability of ectothermic organisms to altered thermal niches. We detected significant directional selection favouring lizards with higher thermal preferences and faster sprint performance at their optimal temperature. Our analyses also revealed correlational selection between thermal preference and critical thermal maxima, where individuals that preferred warmer body temperatures with cooler critical thermal maxima were favoured by selection. Recent published estimates of heritability for thermal traits suggest that, in concert with the strong selective pressures we demonstrate here, evolutionary adaptation may promote long-term persistence of ectotherms in altered thermal environments.

气候变化正引发全球范围内生境热品质的根本性重塑。尽管物种已通过调整分布范围以应对环境变化，但针对气温上升的适应性演化相关证据仍较为匮乏。然而，若要明确生物应对热环境变化的适应潜力，我们需要估算那些被认为可提升生物在暖化环境中存续能力的性状所承受的自然选择强度与方向。当前绝大多数关于生理适应的推论均基于种间分析，而针对热性状的选择作用研究则相对稀缺。本研究针对用于评估变温生物（ectothermic organisms）热生态位改变风险的核心热性状，估算其承受的自然选择作用。研究发现存在显著的定向选择：偏好更高体温、且在最适温度下冲刺速度更快的蜥蜴更受选择青睐。分析还揭示了体温偏好与临界最高体温（critical thermal maxima）之间的相关选择：偏好较高体温却同时拥有较低临界最高体温的个体更受选择偏好。近期已发表的热性状遗传力（heritability）估算结果显示，结合本研究揭示的强劲选择压力，演化适应或可助力变温生物在改变后的热环境中实现长期存续。